Tumors and lesions are types of pathological anatomies characterized by abnormal growth of tissue resulting from the uncontrolled, progressive multiplication of cells, while serving no physiological function.
Pathological anatomies can be treated with an invasive procedure, such as surgery, which can be harmful and full of risks for the patient. A non-invasive method to treat a pathological anatomy (e.g., tumor, legion, vascular malformation, nerve disorder, etc.) is external beam radiation treatment, which includes radiation therapy (radiotherapy) and radiation surgery (radiosurgery). Radiotherapy and radiosurgery differ in the amount of radiation delivered to a patient in a treatment session. The amount of radiation in an individual session or fraction utilized in radiotherapy treatment sessions is typically about an order of magnitude smaller, as compared to the amount used in a radiosurgery session. For convenience, the term “radiation treatment” is used herein to mean radiosurgery and/or radiotherapy unless otherwise noted by the magnitude of the radiation.
Treatment planning is performed to determine the radiation dose that will be delivered to the target region and the radiation dose that will be delivered to surrounding tissue. A conventional treatment planning system, such as that developed by Accuray, Inc. uses an interface that uses 2D input devices such as a mouse or trackpad and monoscopic displays such as a standard computer monitor. Such a treatment planning system is described in U.S. Patent Publication No. 20060274885, entitled, “Treatment Planning Software And Corresponding User Interface,” published Dec. 7, 2006. In such a treatment planning system, image slices are used as a primary working space. Target and critical regions are identified on axial, coronal, or sagittal images slice by slice. Existing treatment planning systems do not provide a virtual environment.